From the beginning bolshevism was for Lenin a purely Russian phenomenon. During the many years of his political activity, he never attempted to elevate the bolshevik system to forms of struggles in other countries. He was a social democrat who saw in Bebel and Kautsky the genial leaders of the working class, and he ignored the left-wing of the German socialist movement struggling against these heroes of Lenin and against all the other opportunists. Ignoring them, he remained in consistent isolation surrounded by a small group of Russian emigrants, and he continued to stand under Kautsky's sway even when the German "left", under the leadership of Rosa Luxemburg, was already engaged in open struggle against Kautskyism.

Lenin was concerned only with Russia. His goal was the end of the Czarist feudal system and the conquest of the greatest amount of political influence for his social democratic party within the bourgeois society. However, it realized that it could stay in power and drive on the process of socialization only if it could unleash the world revolution of the workers. But its own activity in this respect was quite an unhappy one. By helping to drive the German workers back into the parties, trade unions, and parliament, and by the simultaneous destruction of the German council (soviet) movement, the Bolsheviks lent a hand, to the defeat of the awakening European revolution.

The Bolshevik Party, consisting of professional revolutionists on the one hand and large backward masses on the other, remained isolated. It could not develop a real soviet system within the years of civil war, intervention, economic decline, failing socialization experiments, and the improvised Red Army. Though the soviets, which were developed by the Mensheviks, did not fit into the bolshevistik scheme, it was with their help that the Bolsheviks came to power. With the stabilisation of power and the economic reconstruction process, the Bolshevik Party did not know how to co-ordinate the strange soviet system to their own decisions and activities. Nevertheless, socialism was also the desire of the Bolsheviks, and it needed the world proletariat for its realization.

Lenin thought it essential to win the workers of the world over to the bolshevik methods. It was disturbing that the workers of other countries, despite the great triumph of Bolshevism, showed little inclination to accept for themselves the bolshevik theory and practice, but tended rather in the direction of the council movement, that arose in a number of countries, and especially in Germany.

This council movement Lenin could use no longer in Russia. In other European countries it showed strong tendencies to oppose the bolshevik type of uprisings. Despite Moscow's tremendous propaganda in all countries, the so-called "ultra-lefts", as Lenin himself pointed out, agitated more successfully for revolution on the basis of the council movement, than did all the propagandists sent by the Bolshevik Party. The Communist Party, following Bolshevism, remained a small, hysterical, and noisy group consisting largely of the proletarianized shreds of the bourgeoisie, whereas the council movement gained in real proletarian strength and attracted the best elements of the working class. To cope with this situation, bolshevik propaganda had to be increased; the "ultra-left" had to be attacked; its influence had to be destroyed in favour of Bolshevism.

Since the soviet system had failed in Russia, how could the radical "competition" dare to attempt to prove to the world that what could not be accomplished by Bolshevism in Russia might very well be realized independently of Bolshevism in other places? Against this competition Lenin wrote his pamphlet "Radicalism, an Infantile Disease of Communism", dictated by fear of losing power and by indignation over the success of the heretics. At first this pamphlet appeared with the subheading, "Attempt at a popular exposition of the Marxian strategy and tactic", but later this too ambitious and silly declaration was removed. It was a little too much. This aggressive, crude, and hateful papal bull was real material for any counter revolutionary. Of all programmatic declarations of Bolshevism it was the most revealing of its real character. It is Bolshevism unmasked. When in 1933 Hitler suppressed all socialist and communist literature in Germany, Lenin's pamphlet was allowed publication and distribution.

As regards the content of the pamphlet, we are not here concerned with what it says in relation to the Russian Revolution, the history of Bolshevism, the polemic between Bolshevism and other streams of the labour movement, or the circumstances allowing for the Bolshevik victory, but solely with the main points by which at the time of the discussion between Lenin and "ultra-leftism", were illustrated the decisive differences between the two opponents.